Global Patent Index - EP 2857540 A4

EP 2857540 A4 20160302 - STEEL WIRE FOR HIGH-STRENGTH SPRING HAVING EXCEPTIONAL COILING PERFORMANCE AND HYDROGEN EMBRITTLEMENT RESISTANCE, AND METHOD FOR MANUFACTURING SAME

Title (en)

STEEL WIRE FOR HIGH-STRENGTH SPRING HAVING EXCEPTIONAL COILING PERFORMANCE AND HYDROGEN EMBRITTLEMENT RESISTANCE, AND METHOD FOR MANUFACTURING SAME

Title (de)

STAHLDRAHT FÜR HOCHFESTE FEDER MIT AUSSERGEWÖHNLICHER AUFWICKELLEISTUNG UND BESTÄNDIGKEIT GEGENÜBER WASSERSTOFFVERSPRÖDUNG SOWIE VERFAHREN ZUR HERSTELLUNG DAVON

Title (fr)

FIL D'ACIER POUR UN RESSORT À HAUTE RÉSISTANCE PRÉSENTANT UNE PERFORMANCE DE BOBINAGE ET UNE RÉSISTANCE À LA FRAGILISATION PAR L'HYDROGÈNE EXCEPTIONNELLES ET SON PROCÉDÉ DE FABRICATION

Publication

EP 2857540 A4 20160302 (EN)

Application

EP 13797230 A 20130520

Priority

  • JP 2012124581 A 20120531
  • JP 2013044766 A 20130306
  • JP 2013063934 W 20130520

Abstract (en)

[origin: EP2857540A1] A steel wire for spring is provided which exhibits high strength even without adding a large amount of alloy elements, and is for obtaining a cold winding spring having excellent coiling performance and improved hydrogen embrittlement resistance. The steel wire for spring is characterized in that C: 0.40-0.65% (mass%), Si: 1.0-3.0%, Mn: 0.6-2.0%, P: 0.015% or less (exclusive of 0%), S: 0.015% or less (exclusive of 0%), and Al: 0.015 percent by mass or less (excluding 0%) of S, and Al: 0.001-0.10% are satisfied, with the remainder consisting of iron and inevitable impurities, tempered martensite: 70 area% or more and retained austenite: 6-15 area% with respect to the total microstructure, the prior austenite grain size number obtained by a method stipulated in JIS G 0551 is No. 10.0 or more, and the tensile strength is 1,900 MPa or more.

IPC 8 full level

C21D 1/18 (2006.01); C21D 8/06 (2006.01); C21D 9/02 (2006.01); C21D 9/52 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/08 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01); C22C 38/16 (2006.01); F16F 1/02 (2006.01)

CPC (source: CN EP US)

C21D 1/18 (2013.01 - CN EP US); C21D 8/065 (2013.01 - EP US); C21D 9/02 (2013.01 - EP US); C21D 9/52 (2013.01 - CN EP US); C21D 9/525 (2013.01 - EP US); C22C 38/00 (2013.01 - CN); C22C 38/02 (2013.01 - CN EP US); C22C 38/04 (2013.01 - CN EP US); C22C 38/06 (2013.01 - CN EP US); C22C 38/08 (2013.01 - EP US); C22C 38/12 (2013.01 - CN EP US); C22C 38/14 (2013.01 - CN EP US); C22C 38/16 (2013.01 - CN US); F16F 1/021 (2013.01 - US); C21D 2211/008 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DOCDB simple family (publication)

EP 2857540 A1 20150408; EP 2857540 A4 20160302; CN 104321454 A 20150128; CN 104321454 B 20160817; JP 2014005532 A 20140116; JP 5364859 B1 20131211; KR 20150002848 A 20150107; MX 2014014448 A 20150805; TW 201408802 A 20140301; TW I496924 B 20150821; US 2015101715 A1 20150416; WO 2013179934 A1 20131205

DOCDB simple family (application)

EP 13797230 A 20130520; CN 201380025097 A 20130520; JP 2013044766 A 20130306; JP 2013063934 W 20130520; KR 20147032284 A 20130520; MX 2014014448 A 20130520; TW 102119422 A 20130531; US 201314397734 A 20130520